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    The educational program for children at Thissio Visitor Center

  • Doridis Telescope

    Doridis Telescope

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  • August

    August 2017 | Photo: Theofanis Matsopoulos


    Julius Schmidt, CHARTE DES GEBIRGE DES MONDES, 1878, ΝΟΑ Library

  • simonvouet English2

    Simon Vouet (1590 - 1649), The Muses Urania and Calliope (1634)

    National Gallery of Art, USA

  • Τηλεσκόπιο Αρίσταρχος English

    Aristarchos Telescope, Helmos Observatory

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    Helmos Observatory, Photography: Harry Katzjaeger
    Source: "Top Shots," National Geographic, June 2012

  • Eskimo Nebula NGC2392 English

    Eskimo Nebula (NGC2392), Aristarchos Telescope, Observer: Dr. Ioannis Alikakos (NOA)

    Digital Image Processing: Theofanis Matsopoulos.

  • Μουσείο Γεωαστροφυσικής English

    Geoastrophysics Museum, Thissio

  • Εκπαίδευση στο ΕΑΑ English

    Summer School in Astrophysics

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    Remote Sensing & Earth Observation

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    Greece from the International Space Station

    Photography: Paolo Nespoli, ESA astronaut

  • 3D Sun English

    3D Image of the Sun from the Solar Dynamics Observatory (SDO) mission of NASA.

    Source: NASA's Solar Dynamics Observatory

  • Helicorder English

    Analogue seismograph recorder

  • Geothermal English
  • Παλιρροιογραφος English

    Tide-gauge of the Instittute of Geodynamics at Vlyhada, Santorini.

  • Πειραμα Ulusses English
    Recovered  Ocean Bottom Seismometers on board of research vessel in the frame of the ULYSSES scientific program
  • Meteo historic archive english

    The historic archive of NOA/IERSD with recordings of climatic observations dated from the mid-19th century is one of the oldesr sources of climatic information for Eastern Medirranean.

  • Meteo time-series graph English

    The evolution of the average annual temperature in Athens from the mid-19th century until today, according to the records of the historic station NOA/IERSD (Hill Nymphs Thission).

  • Researchers Night 2014

    Pnyx Hill: Citizens observe the night sky through telescopes of NOA

    Researchers Night 2014

  • Researchers Night 2014

    Pnyx Hill: Citizens observe the night sky through telescopes of NOA

    Researchers Night 2014

A new research article on surface solar radiation trends in Athens by IERSD/NOA researchers

The National Observatory of Athens is the first research Institution created in Greece (1842). Atmospheric measurements at the Athens center (Thission station) have been performed since the late 19th century and the station has been recognized by the World Meteorological Organization among other 60 centennial stations worldwide, for its uninterrupted operation spanning more than 100 years. This is the oldest climatic station in Greece and of the oldest in the Eastern Mediterranean.

Solar radiation related measurements were performed since 1900. These 113-year long measurements (1900-2012) are presented in this work. Surface solar radiation (SSR) variability is presented showing small changes in SSR from 1900 to 1953, with a maximum decrease of 2.9% per decade in SSR when taking in to account the 1910-1940 period. For the 1955-1980 period, a -2% change per decade has been observed, that matches but it is in the lower limit, compared with various European long-term SSR measurement (solar dimming) related studies. For the 1980-2012 period we have calculated a positive change (+1.5% per decade) which is also in the lower limit of the reported positive (brightening period) changes in SSR around Europe. Comparing the 30-year periods (1954-1983 and 1983-2012) we have found a difference of 4.5%. Most of the observed changes in SSR after 1954 can be attributed partly to cloudiness and mostly to aerosol load changes.

You can download the research article from the links below:



For more information please contact the The Institute for Environmental Research and Sustainable Development (IERSD)

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